You can add el_AjaxPostBack function in your add-ons.
This function exist in global.js file in:
/client/script/global.js

This function consists of 4 arguments as follows :
el_AjaxPostBack(obj, FetchScript, PostbackSectionId, Retrieved)

Plugin has a kind of add-on that can be displayed in any part of the website; add-ons that are purely visual are called plugins. For example, the add-on display of the user ip or the add-on display of the number of turbine rotations in the last minute are divided into plug-ins. Plugins are an add-on helper for components and pages; for example, a quick search plugin is a good complement to a search page.